Wireless communication devices are increasingly popular and increasingly complex. For example, mobile telecommunication devices have progressed from simple phones, to smart phones with multiple communication capabilities (e.g., multiple cellular communication protocols, Wi-Fi, BLUETOOTH® and other short-range communication protocols), supercomputing processors, cameras, etc. Wireless communication devices have antennas to support cellular communication over a range of frequencies.
It is often desirable to have communication technologies at specific frequencies, and/or at frequencies that facilitate meeting various design criteria such as communication quality and/or antenna system size. Antenna systems that use millimeter-wave frequencies may provide high-quality communication in a small form factor.